Windsor Art Products and Illinois Molding Company are "sister" companies - Chicago, 8 Illinois.
Windsor Art Products was the "decorative arts" publishing company which was active from the early 1900's through the 1970's - while Illinois Molding Co was the part of the company that made the frames. Decorative art companies purchased rights and/or commissioned artists to produce original art, which they then reproduced on canvas/board that was pressed and/or embossed simulating brush strokes (as if an artist painted had actually painted it). This was done in order to mass produce decorative art - not with intent to defraud people.